My new bronco

Reply Subscribe

Thread Tools

Search this Thread

Oct 12, 2005 | 08:27 AM

danny_g_76

Thread Starter

Senior User

Joined: Jan 2005

Posts: 231

Likes: 0

From: saranac lake

My new bronco

I just got a 79 bronco with a v-8 i dont know if it is the 351 5.8L or the 400. is there some ways i can find this out.
dan

Oct 12, 2005 | 09:50 AM

satx77stepside

Junior User

Joined: Sep 2001

Posts: 97

Likes: 0

Quote:

Originally Posted by danny_g_76

I just got a 79 bronco with a v-8 i dont know if it is the 351 5.8L or the 400. is there some ways i can find this out.
dan

Not really an easy way. I believe about 1/3 of the '79 broncos had the 400 and the other 2/3's had the 351M. The only way to tell the difference is by measuring the stroke. 351M = 3.5", 400=4.0". I'm not sure if there is an easy way to do this without removing the heads. Maybe you can pull a spark plug and measure from TDC to BDC? Can anyone else verify if this method would be accurate enough to work?

Oct 12, 2005 | 10:05 AM

plowpusher

Posting Guru

Joined: Sep 2003

Posts: 1,192

Likes: 1

From: lino lakes, mn

if it's oem motor look mat the door tag it'll tell you otherwise they are pretty much the same appearance wise

Oct 12, 2005 | 12:33 PM

77460f150

More Turbo

Joined: Apr 2004

Posts: 736

Likes: 3

From: South East, Michigan

Try to decode your VIN # at this link http://www.medicine.wisc.edu/~mrm/bronco/ftvin.cgi, that will tell you what it had from the factory. (I'm assuming that its the original engine) I'm sure you have already looked but, I didn't se it mentioned in any of the reply's yet, If it has not been taken off or fell off there should be an engine spec. sticker on the left valve cover (driver's side) that will state the engine CID. Not real sure if it states exact CID or 351M/400M. -Ed

Last edited by 77460f150; Oct 12, 2005 at 12:40 PM.